PHYS 253 Part III: Chapters 4, 12, 13, 14 & 15

Study aid for test #3

The purpose of this guide is to point out key terms, concepts, and principles that you should know. It is by no means a replacement for you notes or the text book. This guide is not all inclusive. It should help you, however, prepare and review for test #3

General Advice:

1. Be able to define key terms at the end of the chapters 3, 11,12, 13 & 14

2. Be able to state the major contribution of astronomers, scientists, etc. in every chapter.

3. Be able to answer all the end of the chapter multiple choice self-test questions.

4. Be able to repeat sample problems done in class.

5. Review your notes and end of chapter summaries.

Chapter 4: Light and Atoms

The Nature of light: Wave or particle ?

http://www.youtube.com/watch?v=DfPeprQ7oGc  Double-Slit Experiment , Polarization

Key Terms: Doppler effect, Doppler shift, destructive and constructive interference, diffraction, dispersion, scattering, reflection, refraction, wave length, period, frequency, nanometer, photon, photoelectric effect, emission spectra, absorption spectra, visible spectra, electromagnetic waves, etc.

Be able to state the contributions of the following scientists in relation to the nature or speed of light: Plato, Newton, Huygens, Maxwell, Einstein, de Broglie, Davison and Germer, Galileo, Roemer, etc.

Be able to use Wien's law and calculate the temperature of an object such as a star given the wavelength at which its radiation has maximum intensity.

Be able to describe the Bohr model of the hydrogen atom and use it to explain emission and absorption spectra.

Be able to explain why the sky is blue and why sun sets are red.

Chapter 12: The Sun, Our Star

Be able to compare the size of the Sun with the Earth.

Give a diagram that show the structure of the sun, be able to label it.

Be able to explain the mechanism by which our Sun generates energy.

Be able to explain why Sun spots appear darker.

Be able to explain why at first the solar cycle was believed to be 11 years and now astrophysicists believe it is 22 years.

Key terms: chromosphere      corona      photosphere       hydrostatic equilibrium           neutrinos          nuclear fusion proton-proton chain        radiative zone        solar flare      solar wind                 prominence

Scientists: Schwabe ,Bethe, etc.

Ch. 13: Measuring the Properties of Stars

Be able to describe how the following stellar properties are measured: see table 12-4)

distance temperature luminosity apparent magnitude absolute magnitude

radius chemical composition spectral class radial velocity mass

Be able to calculate stellar distance when the parallax angle is given.

Be able to calculate the following stellar properties:

    temperature using Wien's law

     radius using Stefan-Boltzmann's law

    radial velocity using Doppler effect

     stellar mass using modified Kepler's 2nd law

Scientists:   M. Saha   Hertzsprung     Henry Russell     Henry Draper   Annie Jump Cannon    Cecilia Payne          John Goodricke

Be able to sketch and label an H-R diagram. (Luminsoity vs Spectral Class)

Be able to define the following terms:

protostar, main sequence, red giant, white dwarf, parsec,

radial velocity,binary stars ,variable stars ,

Be able to state the difference between the following binary stars systems:

visual, eclipsing ,spectroscopic, astrometric, X-ray binary etc. Binary Stars

Chapters 14 & Chapter 15: The Formation, Evolution and Death of stars

Flowchart for stellar evolution  (Print out the PDF file and then go back an click the start button and answer the question.)

State the Chandrasekhar limit. What is its significance

You should be able to describe, with the help of the H-R diagram, how a star with one solar mass is formed (born), how it evolve through the following stages:

interstellar nebula, protostar, T-tauri stars, main sequence, red giant, variable star, white dwarf.

You should be able to state the criteria that forces some stars to end up as white dwarfs while some explode and then end as pulsars and ring nebula. while others end up as black holes .

Be able to explain the source of energy for the following type of stars:

protostar   

mainsequence

 red giant 

  white dwarf  

  pulsar    

black hole   

  mira variable    

neutron star.

Be able to explain what variable stars are and how they cab be used to measure distance.

What are the major accomplishments of the following scientists as it realtes to astronomy.

Chandrasekhar,

Annie Jump Cannon

M. Saha

Jocelyn Bell

Henrietta Leavitt

Cecilia Payne

Stephen Hawking

Hertzsprung-Russell Diagram - NAAP